1. Field of the Invention
The present invention relates to a global positioning system (GPS) log, and more particularly to a GPS log with a power adjusting unit that reduces unnecessary power consumption of the GPS log.
2. Description of Related Art
Conventional global positioning system (GPS) devices are in common use today. A conventional GPS device receives signals transmitted by satellites and computes the transmission time of the signals to determine positions and speed of the GPS device and intensity of the signals transmitted from the satellites.
Conventional GPS logs are electronic products relative to the GPS device. A conventional GPS log comprises an antenna, a GPS module, a memory, a power control module and a main control module. The antenna receives signals transmitted by satellites. The GPS module is connected to the antenna to receive the signals, computes speed and positions of the GPS log and further has a real time clock (RTC) that counts time and date accurately. The power control module is connected between a power source and the GPS module. The main control module is connected to the GPS module and the power control module. The main control module commands the power control module to provide power to the GPS module in a fixed period about 0.5 seconds so the GPS module computes the speed and the positions of the GPS log every 0.5 seconds. The memory is connected to the main module and stores the positions of the GPS log and the time and date until the GPS log is turned off. Therefore, the conventional GPS logs are capable of allowing users to read moving tracks of the GPS log from the positions of the GPS device or download data of the moving tracks of the GPS log to an external computer.
However, the GPS module has great power consumption because of the RTC. Even the GPS module cannot receive signals from the satellites or the GPS log is not moving, the GPS module still operates every 0.5 seconds and stores useless data in the memory. Accordingly, the conventional GPS log has a great unnecessary power consumption.
To overcome the shortcomings, the present invention provides a GPS log with low power consumption to mitigate or obviate the aforementioned problems.